U.S. patent number 6,808,165 [Application Number 10/427,555] was granted by the patent office on 2004-10-26 for apparatus for mixing and introducing gas into a large body of liquid.
This patent grant is currently assigned to Smith & Loveless, Inc.. Invention is credited to Fredric H. Avers, Stephen Dashew, Ernest W Downs, Jack Gorby, David O. Sperber, Jr..
United States Patent |
6,808,165 |
Sperber, Jr. , et
al. |
October 26, 2004 |
Apparatus for mixing and introducing gas into a large body of
liquid
Abstract
An gas diffusion device for introducing gas into a large body of
liquid having at least one diffuser blade that engages over a
mounting tube having a spar affixed to its exterior. A passage in
the diffuser blade is dimensioned to cooperatively engage over the
spar and mounting tube which holds the diffuser blade top surface
at a determined angle once so engaged thereover. Changing the
position of the spar on the exterior of the mounting tube in
relation to the center axis of the mounting tube changes the
resulting angle of the diffuser blade top surface. The diffuser
blade can be attached to a hub mounted on a mainshaft that
automatically cantilevers out of the fluid should compressed gas
supplied to the diffuser blade through the mainshaft cease to avoid
damage to the diffuser blade and diffuser pad on the blade from
particulate in the liquid.
Inventors: |
Sperber, Jr.; David O.
(Huntington Beach, CA), Downs; Ernest W (Cathedral City,
CA), Avers; Fredric H. (Jamul, CA), Gorby; Jack (Los
Angeles, CA), Dashew; Stephen (Tucson, AZ) |
Assignee: |
Smith & Loveless, Inc.
(Lenexa, KS)
|
Family
ID: |
33159439 |
Appl.
No.: |
10/427,555 |
Filed: |
April 30, 2003 |
Current U.S.
Class: |
261/87; 261/120;
261/122.1 |
Current CPC
Class: |
B01F
3/04539 (20130101); B01F 13/0049 (20130101); B01F
2003/04567 (20130101); B01F 2003/04546 (20130101) |
Current International
Class: |
B01F
13/00 (20060101); B01F 3/04 (20060101); B01F
003/04 () |
Field of
Search: |
;261/87,91,120,122.1,DIG.71 ;210/221.2,242.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
195354 |
|
Jan 1958 |
|
AT |
|
2023981 |
|
Nov 1971 |
|
DE |
|
1250266 |
|
Nov 1960 |
|
FR |
|
955879 |
|
Apr 1964 |
|
GB |
|
Primary Examiner: Bushey; Scott
Attorney, Agent or Firm: Wood, Phillips, Katz, Clark &
Mortimer
Claims
What is claimed is:
1. An apparatus for introducing gas into a large body of liquid
comprising: at least one diffuser blade having a generally planar
top wall and having a bottom wall intersecting said top wall; said
diffuser blade having an attachment end and a distal end opposite
said attachment end; an interior cavity of said diffuser blade
defined by the area between said top wall and said bottom wall;
said top wall having a plurality of discharge apertures
communicating therethrough; a blade aperture communicating with
said interior cavity at said attachment end; a mounting tube, said
mounting tube having an first end and a second end and having a
mounting tube center axis therethrough; an axial passage
communicating between said first end and said second end of said
mounting tube; a spar positioned on an exterior surface of said
mounting tube; an engagement passage formed in said interior cavity
dimensioned to engage a distance over said spar and said mounting
tube thereby placing said diffuser blade in a mounted position;
means for cooperative engagement of said diffuser blade in said
mounted position; means for substantially sealed engagement of said
blade aperture with said axial passage; said second end of said
mounting tube adapted for attachment to a rotatable hub having a
compressed air supply with said compressed air supply in
substantially sealed communication with said axial passage at said
second end when so attached thereby allowing communication of said
compressed air supply to said discharge apertures; and means for
adjustment of the position of said spar on said exterior surface to
a plurality of positions around said mounting tube center axis
thereby making the angle of said top wall of said diffuser blade
adjustable when placed in said mounted position.
2. The apparatus for introducing gas into a large body of liquid of
claim 1 wherein said means for adjustment of the position of said
spar on said exterior surface to a plurality of positions around
said mounting tube center axis comprises: a flange attached to said
second end of said mounting tube; said flange having a plurality of
flange apertures communicating therethrough; said plurality of
flange apertures alignable with a plurality of hub apertures by
rotating said flange to allow attachment of said flange to said hub
a plurality of positions; and fastener means to engage said flange
apertures to said hub apertures.
3. The apparatus for introducing gas into a large body of liquid of
claim 1 additionally comprising: an elongated nipple adapted for
attachment to said hub at a first end and having a distal end
opposite said first end; said distal end of said nipple having an
orifice in communication with said compressed air supply; and said
axial passage dimensioned to slidably engage over said nipple when
said nipple is attached to said hub.
4. The apparatus for introducing gas into a large body of liquid of
claim 2 additionally comprising: an elongated nipple adapted for
attachment to said hub at a first end and having a distal end
opposite said first end; said distal end of said nipple having an
orifice in communication with said compressed air supply; and said
axial passage dimensioned to slidably engage over said nipple when
said nipple is attached to said hub.
5. The apparatus for introducing gas into a large body of liquid of
claim 1 additionally comprising: a diffuser pad attached to said
planar top wall adjacent to said discharge apertures whereby
compressed air from said discharge apertures is further diffused
upon exit from said diffuser blade.
6. The apparatus for introducing gas into a large body of liquid of
claim 1 additionally comprising: a diffuser pad attached to said
planar top wall adjacent to said discharge apertures whereby
compressed air from said discharge apertures is further diffused
upon exit from said diffuser blade.
7. An apparatus for introducing gas into a large body of liquid
comprising: at least one diffuser blade having a generally planar
top wall and having a bottom wall intersecting said top wall; said
diffuser blade having an attachment end and a distal end opposite
said attachment end; an interior cavity of said diffuser blade
defined by the area between said top wall and said bottom wall;
said top wall having a plurality of discharge apertures
communicating therethrough; a blade aperture communicating with
said interior cavity at said attachment end; a mounting tube, said
mounting tube having an first end and a second end and having a
mounting tube center axis therethrough; an axial passage
communicating between said first end and said second end of said
mounting tube; a spar positioned on an exterior surface of said
mounting tube; an engagement passage formed in said interior cavity
dimensioned to engage a distance over said spar and said mounting
tube thereby placing said diffuser blade in a mounted position;
means for cooperative engagement of said diffuser blade in said
mounted position; means for substantially sealed engagement of said
blade aperture with said axial passage; a hub, said hub attached to
the bottom end of a mainshaft communicating with a hub cavity; said
axial passage at said second end in sealed communication with said
hub cavity thereby allowing communication of said compressed gas
supply to said discharge apertures; said mainshaft adapted at a top
end to sealed engagement with a compressed gas supply; said
mainshaft rotatably mounted to a frame; means to rotate said
mainshaft; means to support said frame above said liquid; and means
for adjustment of the position of said spar on said exterior
surface to a plurality of positions around said mounting tube
center axis thereby making the angle of said top wall of said
diffuser blade adjustable when placed in said mounted position.
8. The apparatus for introducing gas into a large body of liquid of
claim 7 additionally comprising: said hub having a raised position
above said body of liquid and having a submerged position submersed
in said body of liquid; and said hub biased toward said raised
position by default; and means to maintain said hub in said
submerged position so long as said compressed gas supply is
communicated to said axial passage, wherein said hub will move to
said raised position should said compressed gas supply to said
axial passage cease.
9. The apparatus for introducing gas into a large body of liquid of
claim 8 wherein said means to maintain said hub in said submerged
position so long as said compressed gas supply is communicated to
said axial passage comprises: said mainshaft in cantilevered
engagement with said frame; means to make said top end of said
mainshaft heavier than said bottom end of said mainshaft with said
hub and diffuser blade or operatively engaged thereto; attachment
means having a first position holding said hub submerged and a
second position releasing said hub to cantilever out of said liquid
body; and control means to cause said attachment means to move to
said second position should said compressed gas supply to said
axial passage cease.
10. The apparatus for introducing gas into a large body of liquid
of claim 9 wherein said attachment means is an electro magnet with
said first magnetically holding said hub in said submerged
position; and said control means is a switch which turns off said
electro magnet should said compressed gas supply to said axial
passage cease.
11. The apparatus for introducing gas into a large body of liquid
of claim 7 wherein said means for adjustment of the position of
said spar on said exterior surface to a plurality of positions
around said mounting tube center axis comprises: a flange attached
to said second end of said mounting tube; said flange having a
plurality of flange apertures communicating therethrough; said
plurality of flange apertures alignable with a plurality of hub
apertures by rotating said flange to allow attachment of said
flange to said hub a plurality of positions; and fastener means to
engage said flange apertures to said hub apertures.
12. The apparatus for introducing gas into a large body of liquid
of claim 8 wherein said means for adjustment of the position of
said spar on said exterior surface to a plurality of positions
around said mounting tube center axis comprises: a flange attached
to said second end of said mounting tube; said flange having a
plurality of flange apertures communicating therethrough; said
plurality of flange apertures alignable with a plurality of hub
apertures by rotating said flange to allow attachment of said
flange to said hub a plurality of positions; and fastener means to
engage said flange apertures to said hub apertures.
13. The apparatus for introducing gas into a large body of liquid
of claim 7 additionally comprising: an elongated nipple adapted for
attachment to said hub at a first end and having a distal end
opposite said first end; said distal end of said nipple having an
orifice in communication with said compressed air supply; and said
axial passage dimensioned to slidably engage over said nipple when
said nipple is attached to said hub.
14. The apparatus for introducing gas into a large body of liquid
of claim 8 additionally comprising: an elongated nipple adapted for
attachment to said hub at a first end and having a distal end
opposite said first end; said distal end of said nipple having an
orifice in communication with said compressed air supply; and said
axial passage dimensioned to slidably engage over said nipple when
said nipple is attached to said hub.
15. The apparatus for introducing gas into a large body of liquid
of claim 11 additionally comprising: an elongated nipple adapted
for attachment to said hub at a first end and having a distal end
opposite said first end; said distal end of said nipple having an
orifice in communication with said compressed air supply; and said
axial passage dimensioned to slidably engage over said nipple when
said nipple is attached to said hub.
16. The apparatus for introducing gas into a large body of liquid
of claim 12 additionally comprising: an elongated nipple adapted
for attachment to said hub at a first end and having a distal end
opposite said first end; said distal end of said nipple having an
orifice in communication with said compressed air supply; and said
axial passage dimensioned to slidably engage over said nipple when
said nipple is attached to said hub.
17. The apparatus for introducing gas into a large body of liquid
of claim 1 wherein said angle of said top wall is adjusted to a
zero angle of attack when rotating in said body of liquid.
18. The apparatus for introducing gas into a large body of liquid
of claim 2 wherein said angle of said top wall is adjusted to a
zero angle of attack when rotating in said body of liquid.
19. The apparatus for introducing gas into a large body of liquid
of claim 11 wherein said angle of said top wall is adjusted to a
zero angle of attack when rotating in said body of liquid.
20. The apparatus for introducing gas into a large body of liquid
of claim 1 wherein said angle of said top wall is adjustable to an
infinite number of angles by the change in position of the location
of said spar.
Description
FIELD OF THE INVENTION
The disclosed device herein relates to the field of aeration and
mixing of large bodies of fluid. More particularly, the present
invention is an improved apparatus for the introduction of gas and
dissolved gases into a large body of liquid and for concurrently
providing the ability to mix the liquid in a large body of
liquid.
BACKGROUND OF THE INVENTION
Aeration and mixing have been used for treating water and other
liquids for more than one hundred years. During that time various
devices and methods have been employed for the mixing and aeration
of such large bodies of fluid. Such aeration devices include
compressor/diffusers, surface aerators, turbine/spargers, jet
aerators, blade diffusers, with each having its own utility when it
comes to the task at hand.
Compressor/diffuser type aerators employ a compressor suitable to
the task to force gas through a diffuser located below the liquid
surface. As the bubbles naturally rise to the surface of the liquid
being aerated, gas is imparted from the bubbles into the liquid.
Resulting mixing of the liquid is provided by the hydraulic
resistance of the bubbles as they travel to the liquid surface.
Diffuser type aereators range from coarse bubble to fine bubble
diffusers. Coarse bubble systems as the name implies employ larger
bubbles and are more reliable but less energy-efficient to operate,
when compared to fine bubble systems. Fine bubble diffusing
systems, while at first more energy-efficient, frequently become
fouled or clogged due to the small apertures required to produce
the small bubbles clogging thereby resulting in decreased
reliability. Such fine-bubble diffusers, in particular, are limited
in low volume capability, due to increased fouling problems at
lower gas flow rates.
Compressor diffuser type devices employ a rotating gas diffuser in
the form of a large flat horizontal disk-shaped component.
Compressed gas is therein discharged from porous plates arranged
completely around the circumference of the disk. This type of gas
deployment into the liquid tends to produce gas flow where many of
the bubbles tend naturally to follow in the path of preceding
bubbles which limits the efficiency of the transfer of gas into the
surrounding body of liquid. Such a bubble pattern also tends to
interrupt the effective inflow of liquid into the reactor column
and therefor further limits mixing efficiency. Such a device is
shown in U.S. Pat. No. 3,630,498 (Belinski) which teaches the use
of a small, high-speed rotating mixing and an aerating element
comprising a pair of horizontal radially extending blades or foils.
In operation of Belinski, a partial vacuum is formed in a zone of
cavitation behind the foils. Gas bubbles which emerge from the
blades enter this zone of cavitation and expand due to the reduced
pressure around the bubbles. While expanded, the bubbles are
shattered by hydraulic forces into smaller bubbles. These smaller
bubbles then exit the reduced pressure zone of cavitation and are
further reduced in size as they are subjected to ambient pressure.
Critical to the Belinski patent is the creation of the zone of
cavitation. To create this zone of cavitation in a practical
device, the foils must be short (such as 24 inches) and rotated at
very high speeds (such as 450 RPM). Consequently, such a device is
best suited for a smaller area. If the foils are made appreciably
longer, the energy cost and physical loads of high-speed rotation
quickly become prohibitive.
Surface aerators employ an engine or motor to rotate impellers or
blades near the surface of the liquid body. Such devices
conventionally either lift the water into the air above the
surface, or aspirate air and inject it just below the surface of
the liquid body. Surface aerators in general possess a poor gas
transfer efficiency when compared to fine bubble diffused aeration
systems since they consume more horsepower hours of energy for each
pound of dissolved oxygen they produce. Mixing from surface
aerators is generally limited to liquid at or near the surface of
the body of fluid being aerated. Further, mixing energy tends to be
point limited to positions at or near the impeller. Consequently,
localized zones of high shearing forces tend to damage delicate
floc structures necessary for proper liquid clarification. Further,
surface aerators are generally limited in the length of the shaft
overhang, and shaft bearing life tends to be problematic.
Turbine/Spargers aerators use compressors to force and distribute
gas below the surface of the liquid body. They also employ a
submerged impeller positioned just above the diffuser(sparger), to
shear the bubbles and provide bulk mixing of the liquid body in
which they reside. Disadvantages of turbine spargers are similar to
those for surface aerators with the additional disadvantage caused
by the turbine sparger requiring an independent source of
compressed gas such as a compressor.
Jet Aerators employ a liquid pump and an eductor to impart gas into
the liquid body surrounding them using the Venturi principle. Such
a system is taught in U.S. Pat. No. 4,101,286 (Nagao). Such jet
aeration systems may also be equipped to mix additional gas,
liquid, or solid chemicals into the liquid body into which they are
engaged. While such systems are generally reliable and have good
low volume capability, they tend to be inefficient aerators.
Blade diffusers as taught in U.S. Pat. No. 1,383,881 (Ingram) use a
flotation apparatus having rotating blades which dispense gas
bubbles into the surrounding body of liquid. The design of these
blades is dictated, however, by the requirement that they also act
as impellers to rotate the blades as well as discharging the gas
bubbles. Such blades are pitched so that the leading edges are
elevated about 45 degrees and as a result, the emerging gas is
formed into elongated and then enlarged bubbles, which result in a
less efficient introduction of the gas into the liquid. In
addition, examination of the patent and our research indicates that
the blades would rotate in the opposite direction than is indicated
in the Ingram Patent. This would result from the upward flow of
fluid caused by the fluid lift pump effect of the released gas
moving upward toward the liquid surface. Such a vertical water flow
across the pitched blades would appear to in fact cause rotation
opposite that which is taught in Ingram.
Another excellent example of a device for aeration and mixing of
large bodies of liquid is taught in U. S. Pat. No. 5,681,509
(Bailey). Bailey teaches an apparatus and method for mixing and
introducing gas into a large body of liquid by rotating a plurality
of permanently mounted spoke-like discharge members which are below
the surface of the liquid body. These members have upwardly facing
perforated discharge surfaces through which compressed gas is
released up into the liquid. Upward lift is countered by angling
the members which are tilted with their leading edges lower than
their trailing edges and balancing the rotation speed to achieve
substantially zero lift. A control system is provided to change the
depth of submergence of the discharge members to regulate dissolved
gas infusion rate and speed of member rotation to maintain angle of
attack. Bailey, while a leader in this field, teaches the use of
permanantly mounted blade members which are self supporting for the
load forces encountered and which can prove labor intensive to
change if needed. Bailey also teaches the use of a vertically
inclining main shaft which, while providing valuable utility in the
ability to raise the blade members from the liquid in which they
rotate, does require a substantial frame and mechanical structure
to support the components allowing for the inclining main
shaft.
As such, there exists a need for a device for mixing and for
introducing gas into a large body of liquid which is easily
servicable and energy efficient. Such a device should provide
maximum aeration and mixing to the water to which it is immersed
and also provide easy ingress and egress of the diffuser blades
from the water or liquid being aerated. Such a device should best
use diffuser blades that are adaptable for attachment and use with
prior systems for aeration to improve on their performance as well
as in new installations with frame components designed to further
enhance the aeration, energy, and servicing characteristics the
device offers. Such a system would best use diffuser blades which
are light weight due to transference of loading to load bearing
members thereby reducing costs of manufacture and aiding in ease of
installation.
SUMMARY OF THE INVENTION
The device as herein disclosed features an improved diffuser blade
that provides excellent aeration characteristics as well as a
highly improved mounting scheme to the rotating hub which provides
both compressed gas and rotation to the diffuser blade. The
improved mounting system of the diffuser blade enhances both
installation of the diffuser blades during the initial installation
as well as during removal and reinstallation for maintenance. The
improved diffuser blade is mounted on the disclosed support and
operating structure and yields maximum utility due to the combined
characteristics of the tilting support structure and easily
mountable diffuser blades. Or disclosed diffuser blades may also be
used to improve currently installed rotational aeration devices if
adapted for cooperative installed engagement with aeration systems
already in existence to thereby enhance the performance and improve
the serviceability of such existing systems.
The disclosed device herein consists of two main components in the
form of a support frame which floats upon the liquid and diffuser
blades which rotate when immersed in the liquid to aerate the
liquid. The frame is mounted upon a means for floatation or
continued elevation above a liquid pool such as pontoons or on
another means to elevate it above a liquid pool such as a bridge or
pier, and provides a platform for a tilting main shaft, a
connection to a compressed air source, and a means to rotate a
tiltable vertical main shaft such as an electric motor. The frame
component features a unique attachment to the main shaft in that
the main shaft is rotationally engaged with the frame and can be
tilted or cantilevered upward and out of the water or liquid to
either mount or service the diffuser blades to the main shaft or
during power failures or other times when the diffuser blades need
to be raised from the liquid to protect them from clogging.
The diffuser blades attached to the lower or distal end of the main
shaft employ a rectangular spar which is cooperatively engaged
about its outer surface in a similarly shaped passage formed
internally on the diffuser blade. The blade engaging spar is
attached in a fixed position about the exterior surface of a
mounting tube which either mounts directly to the hub of the main
shaft or the mounting tube overlaps a nipple protruding from the
hub which is attached to the main shaft. Once engaged for rotation
by the main shaft, the mounting tube and spar project substantially
normal from the center axis of the main shaft. A pair of
cooperatively engageable mounting collars with one affixed on the
mounting tube and the other upon the mounting end of the diffuser
blade, allow for attachment of the diffuser blade with the mounting
tube with the spar engaged with both the exterior of the mounting
tube and internally on the diffuser blade. The spar being engaged
in a cooperatively engaging passage in the diffuser blade, provides
structural support to the diffuser blade during rotation through
the fluid and provides support to the diffuser blade in maintaining
the angle of attack during rotation in the liquid.
This novel interlocking of the spar with the mounting tube and
using a co-operatively engaging passage axially located in the
diffuser blade, to engage the diffuser blade upon the spar, allows
for easy mounting and dismounting of the diffuser blade to the
mounting tube and spar, for both installation and for maintenance
or replacement. Further, the provision of the metal spar, which
cooperatively engages internally with a passage in the diffuser
blade, provides reinforcement to the diffuser blade against the
plurality of vector forces imparted upon the diffuser blade when
rotating at the determined best angle of attack through the fluid
in which it is immersed. This spar and diffuser blade engagement
transfers a substantial portion of the vector forces imparted to
the diffuser blade including the twisting force and the lateral
force imparted to the diffuser blade at the angle of attack during
rotation of the main shaft in operative communication with the
mounting tube and the nipple. This transfer of force using the spar
engaged in the cooperative passage thus allows the diffuser blade
itself, and its mounting collar, to be made from much lighter
material than if the diffuser blade was required to support the
twisting and lateral forces generated by rotating at an angle in
the fluid. Further, the current preferred spar engaging the
cooperative passage in the diffuser blade has a generally "u" shape
about it and provides an excellent path for disbursement of
compressed gas communicated through the center of the mounting tube
up and through the face of the diffuser blade.
The attachment of the diffuser blade engaged over the rectangular
shaped spar on the mounting tube, using the mating mounting collars
to primarily maintain the diffuser blade upon the spar, also allows
for the diffuser blade to be operatively positioned at a determined
angle of attack when circulating through the fluid. The desired
angle of attack may be achieved using one or a plurality of
provided means for rotational engagement of the diffuser blade to
the hub. This angle of attack is determined by either first
positioning of the spar on the mounting tube in a fixed attachment
such that it is at the proper angle to maintain the diffuser blade
at the desired angle of attack when inserted thereover, or by
taking a mounting tube with an affixed spar thereon, and
cooperatively engaging it with the hub with the spar at the correct
point to yield the proper angle to an attached diffuser blade.
Either means to fix the spar at the proper angle extending from the
hub could be used and yield a diffuser blade engaged over the spar
with the diffuser blade at the desired angle of attack with the
spar absorbing most of the force imparted to the diffuser blade
from circulating angled in the fluid.
In order to maximize the shearing effect of the flow of liquid
relative to the rotating diffuser blades, it is desirable that the
resultant angle of attack of the discharge surfaces of the diffuser
blades, with regard to the relative liquid flow, be essentially
zero or somewhat greater. In other words, such flow should be
generally parallel to or tangential to such surfaces. To achieve
this zero angle of attack the illustrated device is designed to
take into account the effect of the upward discharge of gas from
the diffuser blades. This discharge of gas causes an upward flow of
the liquid in a cylindrical or reactor column that is an upward
extension of the circle defined by the area between the center axis
of the main shaft to the tips of the rotating diffuser blades.
Specifically, such discharge of gas produces a zone of liquid above
the diffuser blades, which due to the presence of gas bubbles in
that liquid, is less dense than the ambient liquid below the
diffuser blades. This less dense liquid is displaced vertically
upwardly from below by ambient density liquid. The vertical upward
flow of the less dense liquid is called the lift pump effect. The
ambient liquid that displaces the rising less dense liquid enters
the reactor column between the rotating blades. This upward flow of
ambient liquid affects the angle of attack between the rotating
blades and the ambient liquid.
To achieve the desired zero angle of attack, in view of the
aforementioned lift pump effect, the diffuser blades in the current
best mode of the device, cooperatively engage through a formed
internal passage, with the exterior of the rectangular spar which
itself is in registered permanent engagement using welding or
attachment components to fix it on the exterior of the mounting
tube. Mating mounting attachment collars attached at the proper
position to the exterior of the mounting tube and formed at the
attachment end of the diffuser blades, hold the diffuser blade from
sliding off the supporting spar during rotation in the fluid. The
engagement of the internal passage of the diffuser blade over the
rectangular spare, which has been properly positioned by affixing
it at the correct position on the tube, or by rotating the mounting
tube to place the spar in the correct position and then attaching
it to the hub, maintains the diffuser blades fixed in a tilted or
pitched position with the leading edges of the diffuser blades
lowered to a determined angle to yield the zero angle of attack
based on a number of factors noted below. The spar as noted must
either be attached to the mounting tube at an angle, or rotated
with the mounting tube which is then attached to the hub when the
spar is properly positioned, such that, when the spar engages with
the passage on the interior of the diffuser blade, the zero angle
of attack is achieved.
The provision of the easily mounted and dismounted light weight
diffuser blade over the spar, and engaged at a determined fixed
angle thereon, provides the ability of the diffuser blades to be
installed to yield an infinite number of different angles of attack
when attached to the mounting tube and adjusted as needed. This
angle adjustment is achieved simply by attaching the spar to the
mounting tube, by welding or bolting or other means to hold the
spar engaged with the mounting tube at the proper determined angle,
in such a manner as to yield the desired angle of attack of the
diffuser blade when it is cooperatively engaged over the spar. Or
as noted, the spar can be affixed to the mounting tube, and then
the mounting tube can be attached to the hub with the spar at
correct position using a means for engagement of the hub to the
mounting tube that will allow for adjustment of the position of the
spar before it is fixed to the hub. Changing the angle of
engagement of the rectangular spar by either rotating the mounting
tube and affixing it to the hub, or by using a mounting tube with
the spar positioned properly for a non rotational attachment to the
hub, results in a changed angle of attack of the engaged diffuser
blade. Of course, in addition to using a means to rotate the
mounting tube and then engage it with the hub, the mounting tubes
can also be manufactured with the spars attached at different
angles to thereby yield the proper angle of attack of the attached
diffuser blades. This makes changing the angle of attack of the
diffuser blades to the indented purpose easily accomplished by
simply changing the mounting tube to one which has the spar
attached at the proper angle to engage the diffuser tube and yield
the desired angle of attack.
Thus the diffuser blades may be easily manufactured of lightweight
material with a properly dimensioned spar engaging passage and
attachment collar and be used in a wide variety of liquids and at
varying speeds and still yield the proper angle of attack simply by
properly attaching the mounting tube to its engagement with the hub
to yield the properly angled or positioned spar attached to its
exterior. Adjustment of position of the spar to the proper point to
engage the diffuser tube interior and hold the diffuser tube at the
proper angle of attack is aided by the provision of a hub flange
which attaches using fasteners to a mating flange affixed to the
mounting tube. The hub flange is provided with a plurality of
different hole combinations in the flange which will align with the
holes formed in the mating flange to allow the mounting tube, and
attached spar to be rotated into the proper position and held in
that position by bolts or other fasteners affixed through the
properly aligned holes in the hub flange and mating flange. By
placing a plurality or large number of different holes in the hub
flange, which when aligned with the mating flange will position the
spar at varying positions about the center axis running from the
hub through the mounting tube, great adjustability for the
resulting angle of attack of the diffuser blade is achieved as well
as providing substantial structural support to the diffuser blade
from the properly positioned spar. Alternatively, these mounting
tubes with attached spars could be manufactured in kits with each
kit having spars positioned at different angles around the center
axis of the mounting tube when attached to the hub directly. While
this would eliminate the need for the plurality of different hole
mating combinations between the hub flange and mating flange, and
is anticipated by this patent, the preferred embodiment employs the
hub flange with multiple alignable holes mating to the mating
flange because of its adjustability which is especially important
during installation and maintenance.
An object of this invention is the provision of an easily mounted
and dismounted diffuser blade for rotation in a fluid to both mix
the fluid and discharge gas into the fluid from the diffuser
blade.
An additional object of this invention is the provision of such a
diffuser blade that is light weight due to the provision of an
internally engageable spar which reinforces the diffuser blade
against rotational and lateral force generated when moving through
a liquid.
Another object of this invention is the provision of a diffuser
blade that is easily slid upon and engaged over a cooperatively
engaging spar which will then maintain the angle of attack of the
diffuser blade when rotating in the fluid.
A further object of this invention is to provide a diffuser blade
that may be easily changed by slidably engaging the diffuser blade
to and from its internal spar engagement.
Yet another object of this invention is the provision of a frame
having a main shaft for rotating the diffuser blade in a fluid
which may be cantilevered out of the fluid for maintenance or
replacement of the diffuser blades.
A further object of this invention is to provide a fail safe system
of fluid aeration wherein the diffuser blades aerating the fluid
will cantilever out of the fluid should power to the air blower
cease, thereby preventing clogging of the diffuser blades.
Yet another object of this invention is to provide a diffuser blade
that is slidably mountable to a mounting tube and secured at the
proper angle of attack for rotation and being able to change the
angle of attack of the diffuser blade by simply changing or
rotating the mounting tube in its affixation to the hub to yield a
differently angled spar.
These together with other objects and advantages which will become
subsequently apparent reside in the details of the construction and
operation as more fully hereinafter described and claimed,
reference being made to the accompanying drawings forming a part
thereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and form a
part of this specification, illustrate embodiments of the invention
and together with the description, serve to explain the principles
of this invention.
FIG. 1 depicts a view of the aeration system herein disclosed
showing improved diffuser blade affixed to a support shaft on a
support frame with the diffuser blade in a submerged position.
FIG. 2 depicts a view of the aeration system herein disclosed
showing the diffuser blade affixed to the support shaft in a raised
position.
FIG. 3 depicts a top view of the diffuser blade engaged with the
mounting tube.
FIG. 4 depicts a side cut away view of the diffuser blade showing
the elongated spar engaged with both the mounting tube and the
interior of the diffuser blade.
FIG. 5 shows an exploded view of the diffuser blade from the spar
engaged upon the mounting tube.
FIG. 5a depicts the hub and the engagement of the mounting tubes to
the hub using angle adjusting hub flanges.
FIG. 6 is a side cut away view along line 6--6 of FIG. 3 depicting
the internal engagement of the spar and mounting tube.
FIG. 7 depicts the hub flanges which provide a plurality of
mounting holes aligned to vary the angle of an attached mounting
tube.
FIG. 8 depicts a vector analysis of the proper angle of attack of
the diffuser blade when moving through the fluid.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, wherein similar parts of the
invention are identified by like reference numerals, there is seen
in FIGS. 1-8 the various components of the disclosed device 10 that
combine to yield an improved apparatus for both mixing and
introducing gas into a large body of liquid such as a lake,
reservoir, or sewage pond where proper aeration is a constant
concern. As noted above the disclosed device 10 consists of two
components including the spar supported diffuser blade 12 which
rotates submersed in the liquid 14 and the support frame 16 which
serves as a floating or elevated mount for the diffuser blade 12
above the liquid 14. As described above the improved diffuser blade
12 and its unique spar engaging and supporting mounting system can
be used to improve the performance and ease the maintenance of
older gas mixing systems by adapting it for attachment to such
systems using the unique spar 42 affixed to the mounting tubes 40
which would be adapted for attachment to existing devices and as
such it could thus be used by itself without the support frame 16.
However, when combined with the unique support frame 16 and with
the components and cantilever ability of the disclosed support
frame 16, the diffuser blade 12 and support frame 16 combine to
yield exceptional function and utility in aeration, maintenance,
and safety.
The support frame 16 is best depicted in FIGS. 1 and 2, is designed
to provide supported above, or float upon, the liquid 14 pool and
thereby provide the platform for the various described components
herein to rotate the diffuser blades 12 submerged in the liquid 14.
The support frame 16 is adapted to maintain a position above or
float upon the surface of the liquid 14 which in the depicted
embodiment uses a means to maintain the frame in position over a
liquid pool such as pontoons 18 which are attached to a base 20.
The pontoons 18 or other flotation means would have sufficient
flotation ability to carry all of the weight of the various
components mounted on the support frame 16. Of course those skilled
in the art will realize that a pier or bridge or cable support
system or other means to maintain the frame in position elevated
above the liquid 14 could be used, and such are anticipated.
A main shaft 22 is rotationally attached to the support frame 16
using a means for rotational engagement of the main shaft 22 with
the support frame 16 which in the current embodiment is
accomplished by hinge 24 which engages a collar 26 surrounding the
upper portion of the main shaft 22 which is rotationally engaged
therein. Consequently, rotating the collar 26 from a position
perpendicular to the surface of the liquid 14 to a position
substantially parallel to the surface of the liquid 14 will thus
cantilever the main shaft 22 from a submerged position shown in
FIG. 1 to an elevated position shown in FIG. 2. In the elevated
position the main shaft 22 will still rotate to thereby ease the
installation and maintenance process when attaching the diffuser
blades 12 to their sealed engagement with the main shaft 22.
In a current preferred mode of the device 10 the rotation of the
main shaft 22 between the elevated position and the submerged
position is achieved by a cable 28 engaged with a winch 30 which is
user activateable. To rotate the main shaft 22 to the submerged
position, the winch is energized and the cable 28 is wound on the
winch 30 and the main shaft 22, which is rotationally engaged
inside the collar 26, is pulled into the liquid 14 when the collar
26 descends, thus submerging the diffuser blades 12 which are
affixed to the distal end of the main shaft 22 into the liquid
14.
Also in a preferred mode of the device 10 the main shaft 22 is
counter balanced using weights or components of the device 10
itself such as pump 32 or other means render the main shaft 22
substantially top heavy at the end above the frame 20. This counter
balance is best if it has sufficient weight to generate sufficient
force whereby the main shaft 22 will default to and rotate to the
elevated position unless pulled and held in the submerged position.
Consequently, in the submerged position in the liquid 14, the main
shaft 22 with the diffuser blades 12 attached, will only remain
submerged so long as a means to rotate and hold the mainshaft in
the submerged position is engaged such as the cable 28 or a similar
tether means is wound on the winch 30 and locked in position around
the winch 30, or if the cable is wound upon the winch and another
locking means is engaged to hold the mainshaft 22 in the submerged
position. As such, in a current preferred mode of the device 10,
the main shaft 22 with one or a plurality of diffuser blades 12
attached, will always default to the elevated position, unless held
submerged by a means to rotate and hold the main shaft 22 in the
submerged position with the main shaft 22 is substantially
perpendicular to the base 20. Defaulting to the elevated position
insures that the diffuser blades 12 are always removed from the
fluid 14 when the compressed air source communicating compressed
air through the diffuser blades 12 and through the diffuser
material 53 into the surrounding liquid 15 ceases. This prevents
particulate in the fluid from clogging the diffuser material 53
mounted over the apertures 52 in the top of the diffuser blades 14
when compressed air is not available and being communicated through
the apertures 52 and the diffuser material 53.
Currently the preferred means to maintain the main shaft 22 in the
submerged position is an electro magnet 34 which contacts the
collar 26 or a mating plate thereon, and holds the main shaft 22
perpendicular to the base 20 only as long as electrical power is
provided to that electro magnet 34. It would be best if the electro
magnet 34 and the pump 32 are both energized by the same electrical
force. If for some reason the electrical power fails to the pump
32, which because of the potential for particulate clogging the
diffuser blade 12 is hazardous the diffuser blade 12, the magnet 34
will cease to function concurrently or just before the positive
pressure from the pump 32 ceases and the main shaft 22 and diffuser
blade 12 will rotate to the default elevated position with both
elevated out of the liquid 14. Of course those skilled in the art
will realize that other means to maintain the main shaft 22 in the
submerged position such as a solenoid, electrical locking mechanism
for the cable 28 or winch 30, or other devices might be used and
consequently such are anticipated in the scope of this patent.
The main shaft 22 is an elongated tube having axial passage
defining a conduit running axially therethrough which communicates
in a sealed engagement at the top end with a pressurized air source
such as compressor or pump 32. As shown in FIG. 1 the pump 32 if
mounted at the top end of the main shaft 22 also provides some or
all of the counter weight to rotate the main shaft 22 to the
default elevated position should electrical power fail thereby
disengaging the electro magnet 34 or any other means to maintain
the main shaft 22 in the submerged position. However weights could
also be used alone or in combination with the pump 32 to yield the
proper force as a counter weight. Also weights alone might be used
as the counter weight and a hose (not shown) might be attached
between a remote compressed air source and the main shaft 22 to
thereby provide a compressed air source into the conduit running
axially through the main shaft 22 for communication of compressed
air to the attached diffuser blades 12 at the distal end of the
main shaft.
Rotation of the main shaft 22 which in turn rotates the diffuser
blade 12 at the distal or lower end of the main shaft 22 is
provided by a means to rotate the main shaft 22 which as depicted
is provided by a motor 33, engaged with the upper end of the main
shaft 22 using a gearbox 36 or similar means for engagement of the
motor 33 to rotate the main shaft 22. In cases of an electrical
motor a motor controller would be used to control the rotation
speed imparted to the main shaft 22 by the motor 33 to achieve the
proper speed of the diffuser blades 12 in the liquid 14 at the
chosen angle of attack of the diffuser blade 12. If course other
types of motors might be used such as compressed air, hydraulic, or
internal combustion motors with the appropriate rotation speed
control means and such are anticipated.
At the lower end of the main shaft 22 a hub 38 is located which has
a plurality of mounting tubes 40 attached to the hub 38 using a hub
flange 41 which would bolt or otherwise be attached to the hub 38.
The hub flange 41 provides an easy means to attach the mounting
tube 40 to the hub 38 and the plurality of holes 58 in the hub
flange 41 provides a means to rotate the mounting tube 40 to
position the spar 42 at the proper point around the center axis of
the mounting tube 40 to engage the diffuser blade 12 and hold it in
place at the proper angle of attack. Or should additional support
be desired, the mounting tubes 40 may be attached to a sealed
engagement with the hub 38 by sliding the passage 51 extending
axially inside the mounting tubes 40 over a plurality of
appropriately diametered supporting nipples 39 projecting
substantially perpendicular to the center axis of the main shaft
22. This would be the case where longer diffuser blades 12 are used
and once slid upon the nipples 39, the hub flange 41 would be
attached to the hub 38 and the position of the spar 42 around the
center axis of the mounting tube 40 would be adjusted to the proper
position wherein the hub flange 41 would be fixedly secured to the
hub 38 thereby securing the mounting tubes 40 to a sealed
engagement with the hub 38. Nipples 39 are used when more support
for the mounting tubes 40 is needed as in cases where longer
diffuser blades 12 or diffuser blades 12 with longer mounting tubes
40 are employed. However, where shorter diffuser blades 12 or
mounting tubes 40 are used and extra support from the nipples 39 is
not required, the mounting tubes 40 could also be directly attached
to the hub 38 by attaching the hub flange 41 to the hub 38 without
the nipples 39.
Each mounting tube 40 has an axial passageway 51 in sealed
communication with the compressed air supply from the conduit
formed internally and running axially through the main shaft 22
through the hub 38 and through a flange aperture 56 communicating
through the hub 38 or from the hub 38 through the distal end of the
nipple 39 if used. Pressurized air or gas is thus communicated from
the pump 32 through the mainshaft 22 through the hub 38 and to the
axial passage 51 extending axially through the mounting tubes 40.
If the nipples 39 are employed, the pressurized air communicates
from the hub 38 through nipple 39 which communicates through the
flange and to the axial passage 51 of the mounting tubes 40. In
this manner, compressed air is communicated from the pressurized
air source communicating with the conduit formed in the main shaft
22 at the top end of the main shaft 22 to the distal ends of each
mounting tube 40 and into the diffuser blades 12 which are in
sealed engagement to the mounting tubes 40.
Attached to the exterior of the mounting tube 40 is an elongated
spar 42 which in the current best mode provides the necessary
structural support to the diffuser blade 12 when frictionally
engaged at the angle determined by the position of the spar 24 in
relation to the center axis of the mounting tube 40. The structural
support of the spar 42 is sufficient to maintain the diffuser blade
12 structurally when exposed to the various force vectors generated
from the liquid 14 being forced against the rotating diffuser blade
12 at the desired angle of attack.
In the current best mode of the device 10 the spar 42 is generally
a "U" shape and as shown in FIG. 6 and fixedly engaged by welding
or other means for fixed engagement, over the exterior
circumference of the projecting mounting tube 40 on one end and
within a cooperating engagement passage 43 axially formed in the
interior of the diffuser blade 12 on the other end, to provide
support to the diffuser blade 12 from both the lateral forces
imparted upon it from rotating in the fluid as well as the twisting
forces imparted upon the diffuser blade 12 from rotating at the
determined angle of attack. Using the slide-on engagement of the
diffuser blade 12 over the spar 42 which is properly mounted on the
mounting tube 40 which is properly attached to the hub 38 using the
appropriate holes 58 to yield the proper angle of attack to the
diffuser blade 12, greatly reduces the time and cost of replacing
or repairing clogged or otherwise impaired diffuser blades 12 and
the cost of the blades themselves since they can be molded from
lightweight material such as plastic which will be sufficient to
hold up to the forces imparted when moving through the fluid 14
with added strength provided by the cooperatively engaged spar 42.
This slidable engagement of the spar 42 inside the engagement
passage 43 axially formed in the diffuser blade 12 and at the
proper angle of attack upon the mounting tubes 40 also allows the
mounting tubes 40 to be pre attached to the hub 38 using the hub
flange 41 or by having the mounting tubes 40 overlap the nipples 39
and attach using the mating hub flange 41. Once the mounting tubes
40 are so mounted, with the spar 42 appropriately rotated to the
proper position to yield the proper angle of attack of the diffuser
blades 12, they provide an easy slid-on target for the unwieldy
elongated diffuser blades 12 over the cooperatively engaging spar
42 during mounting and dismounting which saves time on initial
installation and over the life of the device 10.
Further, by using the spar 42 to carry and transfer to the mounting
tube 40 the majority of the force imparted to the diffuser blade 12
it is easy to change the total length of the diffuser blade 12 to a
longer or shorter total length to match the desired mixing and
aeration for the job intended. A longer diffuser blade 12 is
carried on a longer spar 42 which optionally slides over a nipple
39 for extra support, whereas a shorter one would be supported on a
shorter spar 42 and mounting tube 40 which would attach directly to
the hub 38. As long as the mounting tubes 40 and nipples 39 if
used, are sized to support the force of the longest spar 42 and
diffuser blade 12 that is used, any size diffuser blade 12 below
the longest is easily substituted.
As noted above, the spar 42 is shaped about its circumference to
engage with an engagement passage 43 axially formed inside the
diffuser blade 12. Consequently the angle of attack of the diffuser
blade 12 through the liquid is easily achieved and permanantly
maintained by using a mounting tube 40 which has the spar 42
attached in the proper position to yield the desired angle of
attack of the diffuser blade 12 through the liquid 14 when the
mounting tube 40 is attached to the hub 38. The mounting tubes 40
with a flange 41 affixed to them, are attached to a sealed
engagement with the hub 38 by engaging the hub flange 41 using
bolts or similar fasteners which are locked in engagement with the
hub 38. As can be seen, the hub flange 41 has a plurality of holes
58 which are positioned to line up with appropriately positioned
holes in the hub 38 and position the spar 42 at different positions
depending on the amount of rotation of the mounting tube 40 and the
holes in the hub 38. As can be seen in FIG. 7, a large number of
holes 58 can be placed in the hub flange 41 at both its ends to
allow for a large number of different angles which the mounting
tube 40 may be rotated to thereby rotate the position of the spar
42 about the center axis of the mounting tube 40 and thereby rotate
and maintain the position of the diffuser blade 12 engaged over the
spar 42. Should a different angle of attack be required, the
attachment of the mounting tube 40 to the hub 38 may be rotated one
way or the other by aligning the appropriate holes in the hub
flange 41 and holes in the hub 38 which line up with the holes 58
in the hub flange 41 at differing angles of rotation. Again, once
rotated and attached to place the spar 42 in the proper position to
hold the diffuser blade 12 in the desired proper angle of attack,
that angle of attack is maintained by the spar 42 and diffuser
blade 12 engagement until it is changed by re-mating the hub flange
41 to the hub 38.
The removable attachment of the diffuser blade 12 over the spar 42
and onto the mounting tube 40, is maintained by a means of
attachment of the diffuser blade to the mounting tube using mating
mounting flanges. A first mounting flange 44 mounted about the
circumference of the mounting tubes 40 adjacent to the spar 42
attaches to a second mounting flange 46 formed into or attached to
the mounting end of the diffuser blade 12. Apertures or slots in
both these mounting collars would substantially align so that
fasteners could be placed therethrough thereby providing a means of
attachment of the mounting tube 40 to the mounting end of the
diffuser blade 12. Since the majority of the twisting and other
forces imparted to the diffuser blade 12 rotating at the angle of
attack in the liquid 14 are transmitted to the spar 42 inserted in
the engagement passage 43, the mounting flange 46 on the diffuser
blade 12 is relieved of having to carry this major load and can be
made of lighter material sufficient to withstand substantially the
centrifugal force that might develop and pull the diffuser blade 12
off of its engagement with the spar 42.
The engagement of the mounting flanges 44 and 46 would also
sealably engage the interior cavity 49 of the diffuser blade 12
with the axial passages 51 running the length of the mounting tubes
40 to thereby communicate the pressurized gas or air from the
pressurized air source to the interior cavity 49. From the interior
cavity 49 the pressurized air can them be communicated through
apertures 52 formed in the discharge surfaces 50 of the diffuser
blades 12 and through the adjacent diffuser material 53 and into
the fluid 14.
In order to maximize the shearing effect of the flow of liquid 14
relative to the rotating diffuser blades 12, it is desirable that
the resultant angle of attack of the top surface of the diffuser
material 53 attached upon the upper or discharge surfaces 50 of the
diffuser blades 12 with regard to the relative liquid flow, be
essentially zero or somewhat greater. In other words, such fluid
flow should be generally parallel to or tangential to the top
surface of the diffuser material 53 located upon the discharge
surfaces 50. To achieve this zero angle of attack the disclosed
device 10 is designed to take into account the effect of the upward
discharge of gas from the diffuser blades 12. This discharge of gas
causes an upward flow of the liquid in a cylindrical or reactor
column that is an upward extension of the circle defined by the
area between the center axis of the main shaft 22 to the tips of
the rotating diffuser blades. Specifically, such discharge of gas
produces a zone of liquid above the diffuser blades 12, which due
to the presence of gas bubbles in that liquid, is less dense than
the ambient liquid below the diffuser blades. This less dense
liquid is displaced vertically upwardly from below by ambient
density liquid. The vertical upward flow of the less dense liquid
is called the lift pump effect. The ambient liquid that displaces
the rising less dense liquid enters the reactor column between the
rotating blades 12. This upward flow of ambient liquid affects the
angle of attack between the rotating blades and the ambient
liquid.
To achieve the desired zero angle of attack, in view of the
aforementioned lift pump effect, as noted earlier, the diffuser
blades 12 in the current best mode of the device are mounted over
the spar 42 which has been rotated to the proper position and
secured to the hub 38 by the aforementioned attachment of the hub
flange 41 using the appropriate holes 58 respectively to achieve a
position of the spar 42 which will yield the zero angle of attack
for the diffuser blade 12 when it is engaged over the spar 42.
FIG. 8 illustrates the plane of the discharge surface 50 of the
rotating diffuser blade 12 relative to the resultant vector 61 of
the liquid 14. The resultant vector 61 is the vectorsum of (I) the
horizontal vector 63 produced by the diffuser blade's rotating
forward motion, and (ii) the vertical vector 66 produced by the
liquid column's upward motion. When the angle of the discharge
surface 50 essentially coincides with the angle of the resultant
vector 61, the desirable angle of attack of approximately zero is
achieved. It may be seen from this relationship that, for a given
tilt or angle of incidence of the member surface, the desired zero
angle of attack can be maintained over a range of lift pump effect
vertical liquid flow rates by selectively varying the speed of
rotation of the members. Using the above vector analysis the
relationship between the vector 63 in the horizontal plane
determined by speed of rotation of the blade, the vector 66
determined by the vertical speed of the rising liquid, the angle of
incidence of the blade discharge surface 50, and the vector sum of
the vectors 63 and 66 as represented by resultant vector 61. The
angle at which the rotating inclined diffuser surface 50 is
impacted by the liquid is the angle of attack and is shown as the
angle between resultant vector 61 and surface 50. This angle is
maintained through the life of the blade member 12 by the
engagement of the properly positioned spar 42 with the engagement
passage 43 of the blade member 12.
Compressed gas communicated to the interior cavity 49 of the
diffuser blades 12 from the conduit running through the main shaft
22 is as noted communicated to the interior of the diffuser blades
12 through the generally "U" shaped spar 42 which has an open side
edge along substantially its entire length to thereby aid in the
dispersion of compressed air into the entire length of the interior
cavity 49 of the diffuser blade 12. Once pressurized the interior
cavity 49 communicates the pressurized air through the discharge
material 53 from the plurality of apertures 52 spaced and
positioned to achieve the proper disbursement of gas into the
liquid 14 at the determined angle of attack and speed of the
diffuser blade 12. Between the apertures 52 and the liquid 14 a
diffuser material 53 is attached to the discharge surface 50 of the
diffuser blade 12 provide the proper discharge of compressed air
into the liquid 14. The diffuser material 53 provides proper
defusing of the air into the liquid.
The device herein shown in the drawings and described in detail
herein disclose arrangements of elements of particular construction
and configuration for illustrating preferred embodiments of
structure and method of operation of the present invention. It is
to be understood, however, that elements of different construction
and configuration and other arrangements thereof, other than those
illustrated and described, may be employed in accordance with the
spirit of this invention. All such changes, alterations and
modifications as would occur to those skilled in the art are
considered to be within the scope of this invention as broadly
defined in the appended claims.
As such, while the present invention has been described herein with
reference to particular embodiments thereof, a latitude of
modifications, various changes and substitutions are intended in
the foregoing disclosure, and will be appreciated that in some
instance some features of the invention will be employed without a
corresponding use of other features without departing from the
scope of the invention as set forth in the following claims.
* * * * *